diff --git a/mk/clean.mk b/mk/clean.mk
index f38396cafff..cb8861f6597 100644
--- a/mk/clean.mk
+++ b/mk/clean.mk
@@ -50,7 +50,7 @@ clean-misc:
 	$(Q)rm -f $(RUSTLLVM_LIB_OBJS) $(RUSTLLVM_OBJS_OBJS) $(RUSTLLVM_DEF)
 	$(Q)rm -Rf $(DOCS)
 	$(Q)rm -Rf $(GENERATED)
-	$(Q)rm -f tmp/*
+	$(Q)rm -Rf tmp/*
 	$(Q)rm -Rf rust-stage0-*.tar.bz2 $(PKG_NAME)-*.tar.gz dist
 	$(Q)rm -Rf $(foreach ext, \
                  html aux cp fn ky log pdf pg toc tp vr cps, \
diff --git a/src/libextra/glob.rs b/src/libextra/glob.rs
index 75980497374..6f58102e00a 100644
--- a/src/libextra/glob.rs
+++ b/src/libextra/glob.rs
@@ -448,11 +448,21 @@ impl MatchOptions {
 #[cfg(test)]
 mod test {
     use std::{io, os, unstable};
+    use std::unstable::finally::Finally;
     use super::*;
+    use tempfile;
 
     #[test]
     fn test_relative_pattern() {
 
+        fn change_then_remove(p: &Path, f: &fn()) {
+            do (|| {
+                unstable::change_dir_locked(p, || f());
+            }).finally {
+                os::remove_dir_recursive(p);
+            }
+        }
+
         fn mk_file(path: &str, directory: bool) {
             if directory {
                 os::make_dir(&Path(path), 0xFFFF);
@@ -469,10 +479,10 @@ mod test {
             glob(pattern).collect()
         }
 
-        mk_file("tmp", true);
-        mk_file("tmp/glob-tests", true);
+        let root = tempfile::mkdtemp(&os::tmpdir(), "glob-tests");
+        let root = root.expect("Should have created a temp directory");
 
-        do unstable::change_dir_locked(&Path("tmp/glob-tests")) {
+        do change_then_remove(&root) {
 
             mk_file("aaa", true);
             mk_file("aaa/apple", true);